Ecology #4 [ evolution ] The first wave of evolution is what we think of as Darwinian evolution

Evolution is a gradual process of gradual alteration and takes a long time from simple form, to more complex forms. It takes millions of years for the change to appear more clearly.

The facts show that the living beings of our planetary inhabitants are so diverse that they are affected by the body structure, bodily functions, and behavior of every species (species) of beings. Although among the species of living things are diverse, but the similarity in certain things is still visible. Is not, for example, between a lion and a cat there is a difference in body size and color of hair (hair) on the body, but overall they look very similar ? Based on these facts, scientists try to interpret that the various kinds look the same pattern, so it is supposed to be from the same ancestor. In other words, there is a kinship between each other. This opinion is understood in the theory of evolution.

The evolution of living things is one of the theories studied or studied by Biology. This theory has actually been questioned since the development of science in ancient Rome and Greece, but scientifically this terori has just been put forward by Charles Robert Darwin which is written in a book entitled The Origin of Species by Means of Natural Selection or the Preservation of Favoured Racesin the Struggle for Life, the first edition with the title The Origin of Species published November 24th 1859. Broadly speaking, this theory states that the living creatures that exist in the world up to now is the result of the development of creatures that have existed before, both regarding structure and function, from generation to generation from generation to generation. Therefore, the changes that are the result of that development take place in a very long time, ie millions of years along with the evolution of the universe.

According to Darwin evolution occurs because of natural selection "natural factors capable of selecting living things". Adaptation is the cause of natural selection "natural selection mechanism". It also corrects Lamarck's opinion of giraffes. The long-necked giraffe comes from the long-necked ones as well, while the short-necked ones are destroyed. The factor that led to the evolution of "the mechanism of evolution is natural selection".

From the existing theory, Darwin compiled the evidence and put forward a theory to explain how the evolution took place. He explained the data, which he said as evidence :

1. The reproductive speed of all species exceeds the speed of adding food supplies.
2. All organisms show variation, no two individuals in one species are exactly alike.
3. The more individuals have the opportunity to live, because of the limitations of food, each individual must struggle to survive, supported by: body size, strength, running ability, or any survival traits that cause the individual to have an advantage over others.
4. The features that support survival will be inherited for the next generation.
5. throughout the geologic period, the variations that are able to survive will produce an increasingly obvious distinction, and form new types.

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Sir Alfred Russel Wallace

From his journeys to Malaysia, Borneo, Sulawesi and Maluku, he saw fauna differences in western and eastern Indonesia, bounded by an imaginary line stretching from the north of the sea between the island of Borneo and the island of Sulawesi, stretching south across the Lombok strait. This boundary is deep sea. The funa of Borneo and Bali to the west are Malesiayang type of Asian flora, while the Sulawesi and Lombok fauna to the east are Australasian, similar to the Australian fauna. He also expressed his approval of the concept "Survival of the fittest" as pointed out by Darwin.

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Post Darwin
At this time the scientific community is more communicative, than in the past, so that experts can see the interrelation between science with each other. Invention by Hugo de Vriesdan other at the beginning 1900 provide support for understanding how variations occur in the properties of plants and animals. Natural selection uses these variations to form the diversity of adaptation traits observed in living organisms. Although Hugo de Vries dan genetikawan was initially very critical of the theory of evolution, the rediscovery of genetics and subsequent research ultimately provided a strong basis for evolution, even more convincing than when this theory was first proposed.

Documentation of the facts of evolution is carried out by a branch of biology called evolutionary biology. This branch also develops and tests theories that explain the cause of evolution. The study of fossil records of biological diversity of living organisms has convinced scientists in the mid-nineteenth century that species change over time. But, the mechanisms driving this change remain unclear until the publication of the year 1859 by Charles Darwin, On the Origin of Species which explains in detail the theory of evolution through natural selection. Darwin's work was soon followed by the acceptance of the theory of evolution in the scientific community. In 1930, Darwin's theory of natural selection is combined with the theory of the inheritance of the Book, forming a modern evolutionary synthesis, which links the "gene" evolutionary unit to the mechanism of "natural selection" evolution. The power of explanation and prediction of this theory encourages research that continues to pose new questions, which has become the central principle of modern biology that provides a more thorough explanation of the biodiversity on earth.

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THE THEORY OF EVOLUTION IN THE SCIENTIFIC PERSPECTIVE

rapid technological developments have had an impact on the advancement of science, especially in the hunt for evidence of the evolutionary process. Technology has guided science to be able to trace accurate evidence so that it is undoubtedly scientifically accountable. Thanks to technological dating in the field of radioactive dating, scientists now seem to have the ability to travel far past. Likewise progress in the field of molecular biology. Thanks to that knowledge and the sense apparatus created for it, scientists have managed to uncover kinship relationships that were only traced back to anatomical and morphological similarities.

As more and more new evidence is discovered, the greater the enlightenment we gain in uncovering the evolutionary mystery of living beings. Now, we can not be absent again when science comes to the conclusion that the earth and life on it are the product of evolution, including man as the Caliph on earth.

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Mechanism of Evolution
If the phenotype ratio in a population does not change from generation to generation, it can be stated that the frequency of the population gena is in balance. In other words the process of evolution can be interpreted as a cultivation of allele frequency changes over time. Hardy-Weinberg's law states that the frequency of genes from generation to generation tends to be constant as long as there are no gene mutations, gene recombination, genetic loss (drift) and gene flow. Darwin added that for the occurrence of gene frequency changes there is an environmental role. Through the process of natural selection the direction of evolution is determined.

1. Mutation
   Mutations are random changes in the structure of DNA. Mutation is a rough material for evolution because mutations can cause genetic variation. The cause of the mutation may come from the environment (by mutagenic substances) or changes from within the individual at the time of replication of an error. There are two types of mutations: small mutations and chromosomal changes. In the first case there is a substitution of several nukeotide pairs in the DNA molecule whereas chromosomal changes are major changes involving hundreds or even thousands of nucleotides. The occurrence of mutations can be beneficial or detrimental to the individual who experienced it. Mutations cause changes in genetic variation and are lowered so that mutations have an effect on evolution.

2. Genetic drift
   Genetic drift is the loss of allele frequencies by chance or can be said to be a random change in the frequency of genes in a small population caused by death, migration or isolation. In a small population losing a few of its members will make a big difference. Geneti drift can be caused by two categories of situations the bottleneck effect dan the founder effect.
   The bottleneck effect Natural disasters such as fires, earthquakes, depleted food reserves and epidemic diseases can reduce the number of individuals in the population. The bottleneck effect occurs when very few surviving populations, such as one lecturer left so that the gen pool (the genetic composition of a population) does not represent the initial population.
   The founder effec When a small number of organisms migrate from large populations and settle as new populations in a place where the founder effect can occur. Clearly, the smaller group of migration group genes usually do not represent the large population pool genes. Some alleles will be absent while others will be present in little or excess. As a consequence, when individuals reproduce and the number of founding populations increases, the frequency of genes is different from the initial population.

3. Gen Flow
   Gene flow can occur through interbreeding process. Immigrants can add new alleles to the gen pool so they can change the allele frequency. Gene flow can occur from a very low immigrant range to a very high immigrant range depending on the number of individuals coming in and how many genetic differences in individuals can join. However, if very different genetic information, even small immigration can result in enormous changes in allele frequencies.

4. Sexual Recombination
   In individuals who perform sexual reproduction the resulting offspring may be different from that of the parent because during meiosis the chromosomes are joined randomly and also at the time of the fertilization event occurs the incorporation of genetic material from the two gamete cells. Thus gene recombination can provide a great opportunity for the occurrence of variability that affects population evolution.

5. Natural selection
   Natural selection is one of the factors of evolution, first discovered by Darwin. Individuals who have a match with a survival environment. Therefore nature serves as a selection of the preservation of living things from generation to generation. The result of the adaptation of living things to their environment is called modification and it is inherited in its puppies, so natural selection is a factor of evolution.

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HUMAN EVOLUTION

The process of evolution of living beings with the most attention is the evolution of man. Most people ask whether the present human is an evolutionary product, if yes man certainly originates or evolves from a simpler being, but the view that humans are the product of evolution also carries the consequence that the future human descendants are more perfect beings of man now. Speaking of offspring there are two things that will be passed on to the human puppies of genetic information and non-genetic information. Genetic information is very obvious, but non-genetic information is the result of human interaction with the environment. Because human beings are intelligent creatures making the non-genetically derived information increasingly complex so that the discussion of the development of human evolution is viewed from the psycho-social aspect of bipedal beings to Homo sapien.

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Australopithecines

• It is the oldest upright bipedal creature
• Appears 8-10 million years ago
• Classified as hominid (pre-human)
• Australopitthecus africanus (5.5 million years ago)
• Australopitthecus afarensis (3.5 million years ago)
• Australopitthecus robustus and Australopitthecus boisei (2-1 million years ago)
• Meat-eaters and plant-eaters
• Know the tools of stone to hunt and to fight enemies
• Homo habilis, the most advanced Australopithesin, does not just use tools but also make them.

Homo erectus

• Ape humans that have human characteristics
• Able to make better tools from tools made by Homo habilis with more variety
• Tools of stone and wood
• Know the fire and recognize the fire generator
• Great hunter and have a community
• Meganthropus palaeojavanicus (600-500.000 years agi)
• Homo erectus Pekinensis (500.000 years ago)

Homo Neanthertalensis

• Live about 150,000-60,000 years ago
• Knowing hunting tools, self-defense tools, cutlery, and pots
• Already familiar with the seeds of luminance with the discovery of graves by burial in a respectable way "belief there is life after death"
• Considered as pre-Homo sapien

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CONCLUSIONS OF THEORY DARWIN

1. ALL TENDERGRADE ORGANISMS WERE ADDED
2. ONLY A VARIATION THAT CAN CUSTOMIZE YOU CAN SURVIVE
3. THERE ARE STRAIGHT AGAINST THE ENVIRONMENTAL CHANGE TO BE CONTINUOUS LIFE
4. IN ONE FAMILY ALWAYS HAVE VARIATIONS
5. SOME VARIATIONS ARE SUITABLE FOR INDIVIDUALS FOR CERTAIN LIFE ENVIRONMENT TO PROVIDE THESE INDIVIDUALS CAN BE LIVE AND

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If you Enjoyed this article feel free to check out some of my previous editions of Ecology.

Ecology#1[ Introduction to ecology ]

Ecology#2[ the interaction of organisms with the environment ]

Ecology#3[adattamento di organismi]

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FOLLOW @rabo

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reference

[source]Campbell, N.A., Jane B.R., Lawrence G.M. (2003). Biologi. Edisi Kelima, Jakarta: Erlangga.
[source]Darwin, C. (1959). The Origin of Species by Means of Natural Selection. London: John Murray
http://staff.uny.ac.id/sites/default/files/pendidikan/Ir.%20Victoria%20Henuhili,%20%20M.Si./Evolusi_%20diktat%20kuliah.pdf
https://id.wikipedia.org/wiki/Evolusi
https://id.wikipedia.org/wiki/Charles_Darwin
https://upload.wikimedia.org/wikipedia/commons/d/d4/Alfred-Russel-Wallace-c1895
https://id.wikipedia.org/wiki/Alfred_Russel_Wallace